Pilot interaction with TCAS and air traffic control

The Traffic alert and Collision Avoidance System (TCAS) is often framed as separate to -or opposing -air traffic control, i.e. as a backup, redundant system that invokes resolution advisories (RAs) when all other methods of separation assurance fail. A flight simulator experiment examined pilot interaction with TCAS in the context of a full air traffic environment. This paper will describe how pilot responses to RAs are impacted by immediately-prior interactions with the air traffic controller (notably whether they were provided a call-out of the traffic that then caused a traffic event, could overhear party line information relevant to the build of a traffic event, or received air traffic control instructions just before an RA that conflicted with the RA's advised maneuver). Likewise, this paper will describe how features of the RA impact subsequent pilot communications with the air traffic controller.